What should I be doing?

This is a discussion on What should I be doing? within the Beginner Planted Aquarium forums, part of the Beginner Freshwater Aquarium category; -->
I have 45 Gallon tank that is 22&quot; tall. I have two 36&quot; bulbs 4&quot; above the water line. One is a 21 watt ...

I have 45 Gallon tank that is 22" tall. I have two 36" bulbs 4" above the water line. One is a 21 watt T5 ColorMax and the other is a 39 watt T5HO 6700k bulb. Is my tank considered a low light or high light planted tank?

I've been overdosing with Excel Flourish for the past month to get rid of all the BBA I accumulated while using a CO2 bubble ladder since I started my tank 10 months ago. I realize now that part of the problem was the inconsistant levels of CO2 I was producing, and sometimes I'd go days without any CO2. Well, I stopped doing CO2 and am now just dosing the correct amount of Excel every other day. I still have some BBA left but I don't notice any additional growth, plus I added three cherry shrimp a few weeks back and one of them had babies. It appears that 12 babies survived not being eaten when they were very small and are now big enough to roam the tank without being bothered by the fish. So I'm leaving the remaining BBA on my driftwood for the shrimp as a food source.

My ammonia and nitrites are always 0ppm, and my nitrates seem to always be around 10-20ppm before and 1 day after my weekly 20% water change. I've also been putting in 4mL of Flourish Comprehensive a day after my water changes for the past month as Bryon once suggested.

My question is, if my tank is considered a low light tank, should I even bother putting in Flourish Comprehensive once a week and Excel every other day? My plants seem to grow but very slowly. Should I consider replacing the T5 ColorMax with another 6700k T5HO? My plants seemed to have been growing a lot faster when my tank was newer. Should my bulbs be replaced, they are about 10 months old and are on for 7 hours a day.

It is the ballast, which regulates the amount of electricity that is sent through the mecury vapor in the tube that determines how much light is produced, not the wattage of the tube itself. So, regardless of tube wattage you have functionally either two T5HOs or two regular T5s depending on the type of fixture - HO or not. The former would be considered high light, the latter would be considered moderate light, though there is no set definition of these terms.

If yours is HO it will require more work to keep algea at bay, regular T5s will be more manageable. Use the comprehensive regardless. Opinions differ on the excel, my experience is that it will kill algae and some plants without any significant benefit.

Changing to bulbs of different Kelvin rating will not do much, as that is related to type rather than amount of light.

Slow plant growth may have something to do with some other nutrient deficiency.

The ballast is a Coralife T5 HO dual lamp ballast. I realize that I'm going to have algae, I just want to make sure that I keep my BBA under control. Many months ago when BBA started to appear and spread, I shortened the duration that my lights were on. However, I was still using the CO2 bubble ladder. Now that I'm not doing CO2 anymore and just using Excel every other day along with Flourish Comprehensive once a week, do you think I should increase the time that my lights are so they may grow quicker? I think when I first started my planted tank 10 months ago, the lights were on somewhere between 10-12 hours, I can't remember for sure.

I've never had to deal with BBA, but my guess is that it was caused by excess light, especially if you saw a decrease or slowing of its growth when you cut back on the photoperiod. Seems to me that increasing it again would risk allowing the BBA to resume growth and more light really shouldn't be needed by the plants - 7 hours of dual tube T5HO is plenty of light for most. I would look into something else as the cause of your slow plant growth, like mineral content of the water, use of carbon or similar in your filter, stocking level of the tank

I concur with what Quantum has posted, but I'll just make a couple general observations which may help you understand this a bit better.

You mention slow plant growth, but we've no idea what you may mean by this. "Slow" to one aquarist may not be the same to another, plus the plant species are not known and some grow slower anyway. No do we know all the other factors like fish load, fish feeding, GH of the source water, etc.

Aquatic plants will grow by photosynthesis only if they have sufficient light intensity and all required nutrients in proportion to each other. As soon as any one of these factors is not longer adequate, photosynthesis slows and may even stop. In any planted tank, at whatever level the m ethod (high tech down to low-tech) there has to be a balance between light and nutrients.

Problem algae is always due to light, too much light. This can be the intensity, and/or the duration. If either of these exceeds the available nutrients, plants slow photosynthesis and algae takes advantage. And brush algae seems to be particularly adept at this; it is the only algae I have to watch out for.

I now have two 39 watt T5 HO bulbs over my tank. Turns out the colormax I had was a non ho bulb and gave my ballast some problems from time to time and then the bulb finally burned out. So I now have 1.7 watts per gallon. I am doing 5mL of Flourish Excel every other day along with Flourish comprehensive once a week. I'm starting to see an increase in BBA again. What in the heck should I be doing? I don't want to run a CO2 system. Do I need to replace the t5 ho ballast with just a t5 ballast? Should I increase any other type of nutrient, should I do Excel every day or stop it altogether? I know you're against it, but how do the plants get enough CO2 without Excel if I'm running 1.7 watts per gallon. My lights are on 7 hours, should I drop that to 6?

I reread your 4 part series to maintaining a natural tank. In the nutrient section, you recommended a 2nd dose of comprehenisive 3 days after the first weekly dose.

A comprehensive liquid fertilizer may be used once a week on the day following the partial water change*, and a second dose 3 days later depending upon the response of the plants. The type and number of plants in relation to the light intensity and duration plus the number of fish and organics in the aquarium will determine how often fertilization is necessary to maintain the balance.

I guess I should try this, unless you truly think I should replace my T5 HO ballast with something less intense, which I'm assuming that is what you're going to recommend.

I have the single tube, 30" version of the Coralife non-HO T5 and like it a lot, I think the dual tube version would be very good for your taller tank and would be more manageable in regard to algae than the high output T5s